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My Bridgestone has made it to Karl's so we can custom fit the pipes. The only good thing about this is it's out of my garage for a while. Cause I think it's gonna be a while for those things.
My cb350. I'm getting pretty pissed off about this at this point. Thing was running great before my crash at Frontier Land a couple of years ago. Since then it's been awful. At that time I wanted to put in one of Megacycle's needle bearing kits for the camshaft. So the engine got it's normal winter teardown and put that in along with checking everything else out. Nothing wrong just a general check things and put it back together. What's happening is the camchain is rubbing along the side of the slipper cam chain tensioner. Not really sure at this point what could be causing it. A few weeks ago we tore down the engine, for like the fourth time, and found that the pin that the tensioner pivots on was eating itself into the engine case. And on one side more than the other so it would allow the tensioner to be tilted to one side, i.e. not perpendicular to the crankshaft nor parallel to the direction of the chain. Not sure why but we spent a lot of time and money to fix the problem. We reamed the spot where this pin sits so it would accept a 14mm wrist pin. We then opened up the pivot on the tensioner to ride on the wrist pin. Finally finshed putting the thing together last night, of course Mid-Ohio is this week so no big hurry. Put gas in it pushed it down the driveway to start it around 11:00 PM and within 3 minutes of warming up the same noise was back. The chain must be riding along the side of the tensioner once more.
So now I don't think the wrist pin could have eaten in to the case in that amount of time to cause the tensioner to tilt once more. So now I'm at a loss. When the engine was apart the Megacycle bearing kit was triple checked to be sure it was parallel, so it would not allow the camshaft to be un-parallel from the crankshaft. The crank itself was triple checked to ensure the bearings looked, felt and measured fine on a side to side and top to bottom runout. The sprockets on both the cam and crank don't appear to be moving. So does anyone have any ideas?
Craig
My cb350. I'm getting pretty pissed off about this at this point. Thing was running great before my crash at Frontier Land a couple of years ago. Since then it's been awful. At that time I wanted to put in one of Megacycle's needle bearing kits for the camshaft. So the engine got it's normal winter teardown and put that in along with checking everything else out. Nothing wrong just a general check things and put it back together. What's happening is the camchain is rubbing along the side of the slipper cam chain tensioner. Not really sure at this point what could be causing it. A few weeks ago we tore down the engine, for like the fourth time, and found that the pin that the tensioner pivots on was eating itself into the engine case. And on one side more than the other so it would allow the tensioner to be tilted to one side, i.e. not perpendicular to the crankshaft nor parallel to the direction of the chain. Not sure why but we spent a lot of time and money to fix the problem. We reamed the spot where this pin sits so it would accept a 14mm wrist pin. We then opened up the pivot on the tensioner to ride on the wrist pin. Finally finshed putting the thing together last night, of course Mid-Ohio is this week so no big hurry. Put gas in it pushed it down the driveway to start it around 11:00 PM and within 3 minutes of warming up the same noise was back. The chain must be riding along the side of the tensioner once more.
So now I don't think the wrist pin could have eaten in to the case in that amount of time to cause the tensioner to tilt once more. So now I'm at a loss. When the engine was apart the Megacycle bearing kit was triple checked to be sure it was parallel, so it would not allow the camshaft to be un-parallel from the crankshaft. The crank itself was triple checked to ensure the bearings looked, felt and measured fine on a side to side and top to bottom runout. The sprockets on both the cam and crank don't appear to be moving. So does anyone have any ideas?
Craig
Craig, I forgot if you told me or not....was the tensioner already installed before you went to the needle bearings?
Basically I'm asking if the noise started after you installed just the needle bearing cam....or after you installed the cam and the slipper.
Since you are probably going to have it apart again...do this. At some point in the disassembly or reassembly...while you can set the head with cam...on the cylinders with NO chain installed. Take a straight edge...see if you can lay it along side the cam sprocket and shoot it down towards the crank sprocket....see how they line up. I use a thin hardened steel rod out of a inkjet printer for such things.
This should be possible on the "drive" side of the sprockets where the chain usually has a straight shot down to the crank sprocket...will be difficult to see down in there though.
Are the rocker pads centered on the cam lobes properly? Wonder if megacycle took too much off one end when they did the bearings. Any sign that they messed with the cam sprocket flange on the cam? Is the sprocket nice and flat?
I emailed you after you called with some things. Like I said, if you wanted to bring it up and spend a few hours looking at it, I can be available Sun - Weds.
JohnnyB
Basically I'm asking if the noise started after you installed just the needle bearing cam....or after you installed the cam and the slipper.
Since you are probably going to have it apart again...do this. At some point in the disassembly or reassembly...while you can set the head with cam...on the cylinders with NO chain installed. Take a straight edge...see if you can lay it along side the cam sprocket and shoot it down towards the crank sprocket....see how they line up. I use a thin hardened steel rod out of a inkjet printer for such things.
This should be possible on the "drive" side of the sprockets where the chain usually has a straight shot down to the crank sprocket...will be difficult to see down in there though.
Are the rocker pads centered on the cam lobes properly? Wonder if megacycle took too much off one end when they did the bearings. Any sign that they messed with the cam sprocket flange on the cam? Is the sprocket nice and flat?
I emailed you after you called with some things. Like I said, if you wanted to bring it up and spend a few hours looking at it, I can be available Sun - Weds.
JohnnyB
Guys,
Thanks for all the suggestions and ideas. So now I'm really at a loss. Last night when I got home from work I planned to start the bike get it making the noise, then shut it off. That way when I started dissasembly I'd hopefully see the problem. The only problem was I was no longer able to get it to make the noise. Maybe it's fixed itself. Then again maybe it will blow up down the back straight at Mid-Ohio. I started it up three different times, each time I got it up to operating temp. Had it running at high RPMs, and it never would make the same grinding noise. JohnnyB did point out that the chain actually wears a groove in the teflon in the tensioner (Unga - that's the one I'm using). The last rebuild I put in a new tensioner and ran it about a half dozen laps at NHIS, I guess it's possible that put in an incorrect groove and the other night thats's what was causing the chain to rub on the tensioner. Last night's running caused the groove to be re-worn in the correct spot. Who knows. My plan is to run it this weekend. If it makes the noise then I'll stop and go to the swap meet or stand in the lines to ride the new bikes.
Craig
Thanks for all the suggestions and ideas. So now I'm really at a loss. Last night when I got home from work I planned to start the bike get it making the noise, then shut it off. That way when I started dissasembly I'd hopefully see the problem. The only problem was I was no longer able to get it to make the noise. Maybe it's fixed itself. Then again maybe it will blow up down the back straight at Mid-Ohio. I started it up three different times, each time I got it up to operating temp. Had it running at high RPMs, and it never would make the same grinding noise. JohnnyB did point out that the chain actually wears a groove in the teflon in the tensioner (Unga - that's the one I'm using). The last rebuild I put in a new tensioner and ran it about a half dozen laps at NHIS, I guess it's possible that put in an incorrect groove and the other night thats's what was causing the chain to rub on the tensioner. Last night's running caused the groove to be re-worn in the correct spot. Who knows. My plan is to run it this weekend. If it makes the noise then I'll stop and go to the swap meet or stand in the lines to ride the new bikes.
Craig
One more thing.
Tannermatic - I told you I was in no hurry at all for the fender. So when you get it done you get it done. You got other bigger things to be working on. And it means the sooner you do it then I'll feel guilty and have to put it on the bike.
Craig
Tannermatic - I told you I was in no hurry at all for the fender. So when you get it done you get it done. You got other bigger things to be working on. And it means the sooner you do it then I'll feel guilty and have to put it on the bike.
Craig
Craig,
Seriously...I bet you have it solved. I bet Mike redoing the pivot pin got the tensioner in alignment and like you say...just needed to wear a new groove in the teflon. I KNOW that the chain would initially try to find the first slot it wore....so its probably now running in a new straight track.
I'm betting after a little running time you might notice some slight slack in the chain as it settles into the new groove.
Marty and I brainstormed on the phone for while yesterday trying to come up with something and we couldn't think of anything that Mike wouldn't have probably checked.
Good luck at Mid-O, hopefully you'll have some fun to offset all your recent worries. ( I was ready for your call this morning in case you needed to come up).
JohnnyB
Seriously...I bet you have it solved. I bet Mike redoing the pivot pin got the tensioner in alignment and like you say...just needed to wear a new groove in the teflon. I KNOW that the chain would initially try to find the first slot it wore....so its probably now running in a new straight track.
I'm betting after a little running time you might notice some slight slack in the chain as it settles into the new groove.
Marty and I brainstormed on the phone for while yesterday trying to come up with something and we couldn't think of anything that Mike wouldn't have probably checked.
Good luck at Mid-O, hopefully you'll have some fun to offset all your recent worries. ( I was ready for your call this morning in case you needed to come up).
JohnnyB
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